Finding the Fourth Proportional to 1,116.16, 1,540.27 and 618.77

Step by Step Solution

1. Step 1: Write the proportion equation
   1,116.16 : 1,540.27 = 618.77 : x
2. Step 2: Convert to fraction form
   1,116.16/1,540.27 = 618.77/x
3. Step 3: Cross multiply
   1,116.16x = 1,540.27 × 618.77
4. Step 4: Simplify right side
   1,116.16x = 953,074.02
5. Step 5: Solve for x
   x = 953,074.02/1,116.16
6. Step 6: Final answer
   x = 853.89